Chloroquine for mild to moderately active ulcerative colitis: comparison with sulfasalazine

Chloroquine and hydroxychloroquine have been used successfully in a number of immunological diseases because of their immunomodulatory effect. Preliminary studies have shown them to be effective in the treatment of idiopathic ulcerative colitis. We assessed the efficacy or oral chloroquine in the treatment of idiopathic ulcerative colitis of mild to moderate severity in a randomized, controlled, blinded trial. Forty patients were assigned to receive chloroquine phosphate (500 mg/day) or sulfasalazine (3 g/day). The outcome of therapy was monitored at the end of 2 wk and 4 wk by symptom assessment and sigmoidoscopic examination. An objective scoring system was used for the evaluation, and patients were categorized into those showing complete remission, partially responding, and nonresponders. There was a sequential improvement in the individual scores as well as total activity score in both groups at 2 wk and 4 wk. With chloroquine, 12 patients (60%) showed complete remission at 4 wk, whereas six (30%) had a partial response. With sulfasalazine, 11 patients (55%) had complete remission at 4 wk, and eight (40%) showed partial response. There was no significant difference in the response to the two drugs (p > 0.05). Five (25%) patients in the chloroquine group had side effects, compared with eight (40%) in the sulfasalazine group (p > 0.05). All side effects were minor and transient, not requiring withdrawal of the drug. We conclude that short-duration chloroquine therapy is a safe and effective alternative to sulfasalazine in the treatment of mild to moderately active ulcerative colitis.